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98 th session of the JINR Scientific Council. Nuclear Physics PAC. Road map: general considerations. The PAC appreciates the initiative of the JINR Directorate to define a road map of strategic goals for the Institute’s research programme.
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98 th session of the JINR Scientific Council Nuclear Physics PAC Dubna, June, 2005
Road map: general considerations The PAC appreciates the initiative of the JINR Directorate to define a road map of strategic goals for the Institute’s research programme. It is essential to include practical aspects of this programme, in particular financial and manpower resources in this road map. The vitality of the Institute’s activities demands a focusing of these resources, and this may involve some hard decisions concerning projects of lower scientific merit. It is necessary that the impact of the various themes and projects should be highlighted, including the relevance to the interests of the wider international community in general and of the JINR Member States in particular. In this context the provision, maintenance, operation and development of basic facilities is of course an essential element. Dubna, June, 2005
Laboratory presentations The laboratories presentations (BLTP, DLNP, FLNR, FLNP, LIT) reviewed traditionally their current activities and programmes for 2006. However it felt that in future presentations the strategic goals should be more clearly defined, in terms of the topical basic and applied physics questions to be addressed. The PAC congratulates JINR physicists on their recent achievements and notes in particular the obtaining of a further two events in the Z=118 experiment at FLNR. Dubna, June, 2005
Projects Dubna, June, 2005
First experiments with 6He radioactive beams at DRIBs The first experiments carried out at the DRIBs complex demonstrated a large potential for research with accelerated secondary beams. The presented results of the first experiments with 6He beams are of top quality. The investigation of the 6He break-up gave information on the momentum distributions of the 4He products at low energies. The fusion reaction with 6He showed first conclusive data on this process. Dubna, June, 2005
RIB ACCELERATOR COMPLEX OF THE FLNR (JINR) - DRIBS-1 THE 7Li BEAM INTENSITY: 600 pnA THE 6He BEAM PROFILE: X = 7 mm; Y = 8 mm THE 6He BEAM INTENSITY: 5.106 pps Dubna, June, 2005
Measurement of the energy and momentum of the 6He-beam using the magnetic spectrometer MSP-144 Dubna, June, 2005
MOMENTUM DISTRIBUTIONS - CONCLUSIONS • The narrow width of the momentum distribution of 4He from the breakup of 6He ( = 28±1 MeV/c) gives evidence for the existence of a halo in 6He. • The comparison of the data obtained at 10 MeV/A with data at high energies (50-100 MeV/A) shows that they are practically the same. This means that low energy experiments can be as informative. • The width of the momentum distribution of 4He from the breakup of 6He only weakly depends on the target Z. • The width of the momentum distribution of 4He from the breakup of 6Li ( = 54±3 MeV/c) is evidence that there is an “intermediate” pn-halo in 6Li (Phys. Rev. C51 (1995) 2488; Phys. Lett. B527 (2002) 50). Dubna, June, 2005
EXPERIMENTAL SETUP for measuring excitation functions of fusion reactions Proportional gas chamber Al-Absorber 197Au-foils 206Pb-foils 6He 14 MeV 60 MeV 6He+206Pb 212Po* 6He+197Au 203Tl* 6He+197Au 196,198,199Au Dubna, June, 2005
Sub-barrier Fusion Enhancement : 6He+206Pb 6He+206Pb 5He+207Pb (Q=+5MeV) 4He+208Pb (Q=+13MeV) Dubna, June, 2005 Zagrebaev. PRC 67 (2003)
CONCLUSIONSconcerning fusion and transfer-reaction excitation functions • Enhancement is observed for above-barrier fusion (the 2n-channel for the 206Pb+6He reaction) compared to predictions of the statistical model. • Good agreement is observed with the predictions of the sequential fusion model for reactions of 6He+heavy nuclei (Zagrebaev, Phys. Rev. C67 (2003)). • Transfer reactions – the transfer of 2 neutrons from 6He to 197Au is about 3 orders of magnitude less than the transfer of 1 neutron. Dubna, June, 2005
Recommendation. The research programme with 6He beams should be continued with first priority. Dubna, June, 2005
MUON project “Investigation of the Muon Properties and the Muon Interactions with Matter” The PAC noted with interest the new results obtained in the MUON project during the last three years. Dubna, June, 2005
1. Status of the project Scientific collaboration with: Paul Scherrer Institute(Switzerland) Moscow Institute of Physics and Technology (MFTI, Dolgoprudny) St.-Petersburg Institute of Nuclear Physics (Gatchina) RNC "Kurchatov Institute" (Moscow) Institute of theoretical and experimental physics (Moscow) Max-Plank Institut fur Metallforschung(Germany) Institute of Solid State and Semiconductor Physics of NASB, Minsk Dubna, June, 2005
2. Resent results 2.1 Experiments with negative muons (Dr. T. Mamedov) 2.1.1 Semiconductors 2.1.2 g-factor ofμ- in the bound state 2.1.3 Capture ofμ- by the noble gases isotopes Dubna, June, 2005
2.2 Experiments with positive muons 2.2.1 Magnetism in Holmium Dubna, June, 2005
2.2 Experiments with positive muons 2.2.2Heavy fermions Ce3Pd20Ge(Si)6 “… CePdSi compound is one of the heaviest-electron system with gamma reaching 8 J/ mol Ce K2 at 0.2 K…“ Dubna, June, 2005
3. Status of the set-up Dubna, June, 2005
4. Plans and perspectives We suppose: 4.1 - to continue experiments atPSI (Si, SiC, diamonds, g-factor, …) 4.2 - to renew in Dubna the study of metals and oxides with big samples (Bi2CuO4 Bi2O3 …) 4.3 - to start the study of ferroliquids (Rumania) 4.4 – to continue the activity with polarized targets (Dr. E.I.Bunyatova) Dubna, June, 2005
Recommendation. The PAC recommends continuation of this project. Dubna, June, 2005
SAD project (written report) The PAC welcomes the completion of the design stage of the project “Subcritical Assembly at Dubna” (project SAD), targeted on creating a facility for addressing important problems of modern nuclear energy production and waste transmutation. Dubna, June, 2005
Recommendation. The PAC encourages collaboration between the SAD project and running European and other transmutation projects aimed at establishing closer connection of JINR with the world scientific transmutation community and making it more attractive for Member States. Dubna, June, 2005
New Projects Dubna, June, 2005
PALM project • PALM project proposes a first experiment with positronium beams. In LEPTA the lifetime of the circulating electron beam was significantly increased, and reasonable parameters like UHV requirements for successful future operation were defined. The next step of LEPTA development will be construction of a positronium source, improvement of the vacuum and development of a positronium beam of adequate intensity for the proposed experiment. • The PALM experiment aims at an improved lifetime measurement of para-positronium by a factor of two compared with previous experiments. Although the PAC does not consider PALM to be a significant QED test, it welcomes this experiment as an important first educational step to train the young scientists who have made a major contribution in creating the LEPTA facility. The PAC expects, however, new physics proposals to be formulated in due time. Dubna, June, 2005
Progress on LEPTA: Test of The Lepta Ring with Circulating Electron Beam Electron gun Dubna, June, 2005
Proposal of The Experiment PALM (PArapositronium Lifetime Measurement) Dubna, June, 2005
Experiment PALM (continued) 3.1. Motivation LEPTA The proposed experiment is of a special interest due to two reasons: 1) The theory: QED calculations of parahave been performed by several authors. The most advanced result (para / para)theor = 210-6 was obtained by a single group (see [1] PRL 83 (1999) 1135) and have NOT been confirmed by any others. Corrections of the paratheoretical value have two originations. The first one relates to the relativistic modification of Bethe-Salpeter equation including correction of Coulomb potential. The effect on paravalue is expected to be of the order of (v/c)2 ~ 2 and 3 correspondingly (see Yad. Fiz. v.61, 1990). These effects are not investigated yet properly. The second one is real radiation corrections including up to two-loop analysis. One can suspect that the contribution of the light-light scatteringeffectis underestimated in the paper [1]. (E. Kuraev, BLTP JINR, October 2005) LEPTA Ps Dubna, June, 2005
Superconducting solenoid PMTube BGO-crystal • Fe NbTi 130 mm • • NbTi Fe 150 mm 1 m Target One measures the function • N1(B) – number of detector counts during time interval T1 when solenoid field value is equalto B, • N2 – the count numberduring T2 at B = 0. Experiment PALM (continued) 3.2. Experiment scheme o-Ps/p-Ps o-Ps o-Ps Dubna, June, 2005
~ 9 months. ExperimentPALM: Statistics Requirements(continued) Thus, to obtain the necessary statistic precisionp / p = 1·10-4one requires to register Nexp 41010 events number. Then the experiment duration is defined by the cycle parameters: Cycle duration – 100 s, where 45 s – B-field is ON , 45 s – B-field is OFF , 10 s - transition (switching) time. Besides, during every 45 s one half of time has to be spent for measurement of background(o-Ps is “closed”). If the detector efficiency is ~ 0.7 and average o-Ps flux intensity is of I = 6103 s-1 the full duration of the experiment will be of Dubna, June, 2005
Recommendation. Further development of the LEPTA ring and the PALM proposal as an educational experiment are recommended for approval. Dubna, June, 2005
GERDA–MAJORANA project The PAC recognizes the fundamental importance of modern neutrino experiments and the internationally acknowledged expertise of DLNP staff in this domain. With this in mind, the PAC welcomed the new proposal on the GERDA–MAJORANA project on the search for neutrinoless double-beta-decay of 76Ge. After the latest discoveries of the oscillations in reactor, solar and atmospheric neutrino fluxes, this new type of experiment is an essential next step in neutrino physics, and DLNP’s participation is deemed to be very important. Dubna, June, 2005
G&M Experimental Search for Neutrinoless Double Beta Decay of 76Ge (GERDA-MAJORANA) Participants from Dubna: V.Brudanin, M.V. ChirchenkoI.Chirikov-Zorin, V.Egorov, K.Gusev, S.Katulina, A.Klimenko, O.Kochetov, I.Nemchenok, N.Rukhadze, V.Sandukovsky, A.Smolnikov, Yu.Shitov, V.Timkin, S.Vasiliev, Ts.Vylov, E.Yakushev, J.Yurkowski. Dubna, June, 2005
Double beta bb(0n) decay : experimental observable Dubna, June, 2005
Majorana GERDAGermanium Detector Array for the search of neutrinoless - decays of 76Ge at LNGS The Majorana Zero-Neutrino Double-Beta Decay Experiment & Dubna, June, 2005
Cost estimates & status of funding Cap. Investment Phase I: 6490 kEuro Phase II: 3830 kEuro (~70% of funding secured) Dubna, June, 2005
JINR contribution: • Muon veto (plastic scint.) • Radon detectors • Handling Ge detectors (we have a special group which can do it) • 4 kg of 76Ge → SEGA (Majorana) • Data analysis, simulation, etc. • We’ll see… Dubna, June, 2005
GERDA Collaboration INFN LNGS, Assergi, Italy A.Di Vacri, M. Junker, M. Laubenstein, C. Tomei, L. Pandola JINR Dubna, Russia V. Brudanin, V. Egorov, K. Gusev, S. Katulina, A. Klimenko, O. Kochetov, I. Nemchenok, V. Sandukovsky, A. Smolnikov, J. Yurkowski, S. Vasiliev, MPIK, Heidelberg, Germany C. Bauer, O. Chkvorets, W. Hampel, G. Heusser, W. Hofmann, J. Kiko, K.T. Knöpfle, P. Peiffer, S. Schönert, J. Schreiner, B. Schwingenheuer, H. Simgen, G. Zuzel Univ. Köln, Germany J. Eberth, D. Weisshaar Jagiellonian University, Krakow, Poland M.Wojcik Univ. di Milano Bicocca e INFN, Milano, Italy E. Bellotti, C. Cattadori INR, Moscow, Russia I. Barabanov, L. Bezrukov, A. Gangapshev, V. Gurentsov, V. Kusminov, E. Yanovich ITEP Physics, Moscow, Russia V.P. Bolotsky, E. Demidova, I.V. Kirpichnikov, A.A. Vasenko, V.N. Kornoukhov Kurchatov Institute, Moscow, Russia A.M. Bakalyarov, S.T. Belyaev, M.V. Chirchenko, G.Y. Grigoriev, L.V. Inzhechik, V.I. Lebedev, A.V. Tikhomirov, S.V. Zhukov MPP, München, Germany I. Abt, M. Altmann, C. B\"uttner. A. Caldwell, R. Kotthaus, X. Liu, H.-G. Moser, R.H. Richter Univ. di Padova e INFN, Padova, Italy A. Bettini, E. Farnea, C. Rossi Alvarez, C.A. Ur Univ. Tübingen, Germany M. Bauer, H. Clement, J. Jochum, S. Scholl, K. Rottler 1.8 + 1 4 6 + 2 3 6 + 1 4 1.6 0.3 1.3 2+1 71 physicists listed; 30 full time equivalent staff + 5 PhD students 9.5 FET engineer/technician Dubna, June, 2005
Summary • Collaboration formed: expertise • Aggressive Schedule: start construction summer 2005; first physics 2007 • ~70% of funding secured • Manpower sufficient to get project going: ~30 FTE staff physicist + 9 FTE engineer • Competitive with relevant physics results already in Phase I • Need approval to keep schedule Dubna, June, 2005
Recommendation. The PAC considers the GERDA–MAJORANA project to be of the highest priority for DLNP and recommends its approval Dubna, June, 2005
Development of the “Knowledge Base on Low-Energy Nuclear Physics” The PAC welcomes the initiative of V. Zagrebayev’s team to create a network nuclear physics knowledge base. In particular, the provision of an on-line capability for performing nuclear reactions calculations is unique. The exercise is important to the wider international community and will bring great credit to FLNR. The PAC therefore urges the FLNR Directorate to assist in completing and continuously updating this base. Dubna, June, 2005
Scientific reports The PAC noted with interest the reports • on the resonance states of heavy hydrogen and helium nuclear systems, presented by G. Ter-Akopian, and appreciates the important new results in this field recently obtained at the ACCULINNA set-up. • "First results on fission, obtained at the n_TOF facility" presented by W. Furman. The impressive amount of top-quality nuclear data has been obtained by the collaboration CERN–JINR–IPPE (Obninsk). The PAC supports this activity and looks forward to the complete analysis of the measured data that will confirm their important practical and scientific input. • “Light nucleus clustering in fragmentation above 1 A·GeV” presented by P. Zarubin. Fragmentation of light nuclei has been observed at the Nuclotron beams using emulsion techniques. Inverse information on clustering features of nuclei is deduced. Dubna, June, 2005
First Priority Experimental Tasks Scheduled for IREN with Budget and Manpower Dubna, June, 2005
Members of the PAC for Nuclear Physics • Independent members • Hans Börner * - ILL, Grenoble, France • Rafal Broda* - INP, Cracow, Poland • Jan Dobes - NPI, Řež, Czech Republic • Yury Gaponov - RRC «Kurchatov Iinstitute», Moscow,Russia • Andrei Goverdovski - IPPE, Obninsk, Russia • Natalia Janeva - INRNE, Sofia, Bulgaria • Gottfried Munzenberg - GSI, Darmstadt, Germany • Сlaude Petitjean - PSI, Villigen, Switzerland • Neil Rowley - IReS, Strasbourg, France • Adam Sobiczewski - INS, Warsaw, Poland • Ex officio members from JINR • Michail Itkis - Director, FLNR • Alojz Kovalik - Deputy Director, DLNP • Valery Shvetsov* - Deputy Director, FLNP • Victor Voronov - Deputy Director, BLTP • Tsvetan Vylov - Vice-Director, JINR • Pavel Zrelov - Deputy Director, LIT • __________________________ • *are not present at this meeting Dubna, June, 2005